WASHINGTON (NEXSTAR)— With Election Day less than two months away, both Vice President Kamala Harris and former President Donald Trump are ramping up their campaign efforts in battleground states. Experts point to seven key swing states that could determine the outcome of the election. That, in part, has to do with the Electoral College which allocates a certain number of electoral votes per state based on how many senators and representatives it has in Congress, giving more populated states more electoral votes. Presidential elections are determined based on the electoral vote total, not the popular vote total. Therefore, the candidate who earns at least 270 electoral votes wins the presidency, even if they do not win the national popular vote total. In recent history, there have been two races where the candidate who won the popular vote did not win the election. How do third-party candidates impact elections? In 2000, Democratic candidate Al Gore won nearly 540,000 more votes than Republican candidate George W. Bush. However, Bush won the election because he earned a total of 271 electoral votes to Gore’s 266. In 2016, Democratic candidate Hillary Clinton earned nearly 2.9 million more votes than Republican candidate Donald Trump. Trump won the presidency however because he received more electoral votes than Clinton, earning 304 to her 227. Each state is responsible for totaling the number of votes for each candidate. The candidate that earns the popular vote in that state earns that state’s electoral votes. For example, all 54 of California’s electoral votes go to the winner of that state, even if the candidate only won the state by a small margin. Two states use a slightly different system. Nebraska and Maine allocate two electoral votes to the candidate who wins the state popular vote. They then award one electoral vote to the popular vote winner in each Congressional district. While most states consistently vote along party lines, swing states can vary from election to election. According to political experts, the seven key swing states in the 2024 election are Arizona (11 electoral votes), Georgia (16 electoral votes), Michigan (15 electoral votes), Nevada (6 electoral votes), North Carolina (16 electoral votes), Pennsylvania (19 electoral votes) and Wisconsin (10 electoral votes).